抄録
The emergence of β-lactamase-producing strains of Neisseria gonorrhoeae has led to a reexamination of the role of the disc agar diffusion method in susceptibility testing of gonococci. Our data show that the disc agar diffusion test can be used to screen for β-lactamase production by these organisms. The disc tests were done on GC Agar Base supplemented with 1 % IsoVitaleX. An inoculum of 108 colony forming units/ml and either a 10-unitpenicillin or a 10-μg-ampicillin disc were used. A zone diameter of ≤19 mm was indicative of β-lactamase production. These results were compared with results of chemical tests for β-lactamase and with minimal inhibitory concentrations. Recommendations were also made for a disc test with tetracycline and spectinomycin, but these methods must remain tentative because of the lack of resistant strains.
